Mathews was averaging 20.4 minutes per game entering Sunday night’s game against California and came off the bench to play a key role in the Trojans’ Pac-12 home-opening win over Stanford three nights earlier.

The 6-foot-3 guard poked away four steals.

It was not exactly a breakthrough.

In a win over Wyoming in Las Vegas in late December, Mathews had six steals.

He has been athletic and quick enough with his hands to knock the ball out of the control of offensive players. He has warmed up to defense, too.

“Coach Enfield is a defensive guy, so if you play defense, you’ll play,” Mathews said. “I was like, ‘I don’t want people scoring on me. I don’t like my team getting scored on.’ It was kind of a pride thing.”

As a senior at Santa Monica High a year ago, Mathews was a skilled scorer, averaged 24 points per game and scored as many as 41 points in one contest.

His touch on offense has been a little slower to translate. Through the first 16 games, Mathews was shooting 37 percent.

“He’s a little streaky,” Enfield said. “He’s learning as he goes through his first season what a good shot is. The shooting percentage for a contested jump shot at the college and NBA level is low. When he improves his decision making, when to take a jump shot, when to put the ball on the floor, those shooting percentages should go up, because he is a good stand-still shooter.”

Hard contact

California guard Don Coleman was called for a Flagrant 1 foul with 5:46 left to play in the first half when he knocked over De’Anthony Melton on a fast-break layup attempt.

When Melton, a freshman guard for the Trojans, went up moved toward the basket mid-air, Coleman pushed him with his forearm. Melton fell to the court.